The present invention relates generally to carts, and more specifically to a spray cart adapted for connection between the hitch of a towing vehicle such as a tractor and the hitch of a trailing implement such as a field cultivator or finishing tool.
Chemicals such as herbicides are commonly incorporated in the ground during soil-working operations. When liquids are incorporated, a sprayer and one or more tanks are usually mounted on the tractor or the tillage tool. However, such mounting requires much time and labor and usually the sprayer is not easily detachable to free the tractor or tillage tool for other work. In tool-mounted sprayers, uneven incorporation often results because the tank loses weight as the solution is applied and the weight on the tillage tool decreases.
In an attempt to overcome some of the problems involved with tractor- or implement-mounted sprayers, various cart arrangements have been devised. A typical spray cart includes a transverse frame mounted on at least two transversely spaced caster wheels and has a forwardly extending tongue member which rests on the hitch of the trailing implement. The trailing implement is connected in the usual fashion to the tractor hitch. A tongue mounting bracket is connected to the trailing implement hitch, and the spray cart tongue is pinned to the bracket. With such an arrangement, it is usually difficult to gain access to the tank. To tow the cart away from the implement, it is usually necessary to disconnect the implement from the tractor and then connect up a special hitch structure to the spray cart tongue. Such a procedure is generally time-consuming and inconvenient. Rub plates are generally utilized to center the cart on the implement hitch and prevent interference between the cart and the implement hitch.
In another type of cart, such as exemplified by U.S. Pat. No. 4,426,096, the cart hitch is attached to the tractor hitch, and the implement, in turn, is attached to the spray cart directly rearwardly of the connection to the tractor. This type of structure eliminates need for supporting the spray cart on the implement hitch. However, the cart shown therein is supplied with fixed axle wheels which must be relatively widely spaced to prevent interference during short turns, and the spacing between the wheels cannot be easily adjusted, for example, to permit the wheels to ride between ridges when a ridge type of cultivation is employed. Although other types of spray carts utilize adjustable wheel assemblies, the adjusting structure is usually quite cumbersome and expensive, and the range of transverse adjustment of the wheels is usually limited in an inwardly direction by the end of the tank and by the outer beam of the generally boxed-shaped frame structure in the outward direction.
When the tank cart with caster wheels is being towed without a trailing implement, it is desirable to lock the wheels against castering to prevent instability. Heretofore, various transport lock or breaking arrangements for the caster wheels have been devised, but these generally have been fairly complicated or difficult to operate to lock and unlock the wheels.
It is desirable to provide a cart which is simple in construction and yet rugged in both function and appearance. At the same time, it is desirable to keep the tank as low as possible on the frame without interferring with the implement hitch or with the transverse adjustability of the wheels.
It is therefore an object of the present invention to provide an improved implement cart adapted for connecting between a towing vehicle and a trailing implement.
It is a further object of the present invention to provide a cart which is not supported on the hitch structure of the trailing implement and which is easy to connect and disconnect both with respect to the tractor and to the trailing implement.
It is yet another object of the present invention to provide a spray cart wherein the operator has convenient access to the spray tank. It is yet another object of the invention to provide a spray cart adapted for towing behind a tractor and forwardly of a trailing implement wherein special mounting brackets and/or rub plates are eliminated. It is a further object to provide such a cart which has improved tracking.
It is another object of the present invention to provide a cart wherein the spacing between the wheels is easily adjustable. It is still another object to provide such a cart wherein the wheels are transversely adjustable over a substantial width of the machine without interference from either the tank assembly or the outermost ends of the tank-support frame.
It is yet another object of the invention to provide a spray cart with a pair of caster wheels wherein a simple and reliable adjustment is provided to prevent castering of the wheels.
It is still another object of the present invention to provide a spray cart having a simple tubular frame construction with advantageous hitch and tank-support structure, and wherein the tank is easily accessible by the operator. It is also an object to provide such a cart with a tank support structure which reduces stresses in the tank.